I thought about this and came to the conclusion that it is impossible to give your coins after death without trusting someone other than yourself.

You are either:

• transferring the coins too early or too late with an automated transaction
• trusting your children won't take your coins before you die
• trusting a custodian
• trusting a lawyer
• even with instructions written in a sealed written will, someone besides you needs to know about the will's existence and where it is